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Groundwater from the Mississippi River Valley alluvial aquifer (MRVA) is a vital resource for agriculture and drinking-water supplies in the central United States. Water availability can be limited in some areas of the aquifer by high concentrations of trace elements, including manganese and arsenic. Boosted regression trees, a type of ensemble-tree machine-learning method, were used to predict manganese concentration and the probability of arsenic concentration exceeding a 10 µg/L threshold throughout the MRVA. Explanatory variables for the BRT models included attributes associated with well location and construction, surficial variables (such as hydrologic position and recharge), variables extracted from a MODFLOW-2005...
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Groundwater is a vital resource in the Mississippi embayment of the central United States. An innovative approach using machine learning (ML) was employed to predict groundwater salinity—including specific conductance (SC), total dissolved solids (TDS), and chloride (Cl) concentrations—across three drinking-water aquifers of the Mississippi embayment. A ML approach was used because it accommodates a large and diverse set of explanatory variables, does not assume monotonic relations between predictors and response data, and results can be extrapolated to areas of the aquifer not sampled. These aspects of ML allowed potential drivers and sources of high salinity water that have been hypothesized in other studies to...
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Groundwater is a vital resource in the Mississippi embayment of the central United States. An innovative approach using machine learning (ML) was employed to predict groundwater salinity—including specific conductance (SC), total dissolved solids (TDS), and chloride (Cl) concentrations—across three drinking-water aquifers of the Mississippi embayment. A ML approach was used because it accommodates a large and diverse set of explanatory variables, does not assume monotonic relations between predictors and response data, and results can be extrapolated to areas of the aquifer not sampled. These aspects of ML allowed potential drivers and sources of high salinity water that have been hypothesized in other studies to...
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Groundwater is a vital resource to the Mississippi embayment region of the central United States. Regional and integrated assessments of water availability that link physical flow models and water quality in principal aquifer systems provide context for the long-term availability of these water resources. An innovative approach using machine learning was employed to predict groundwater pH across drinking water aquifers of the Mississippi embayment. The region includes two principal regional aquifer systems; the Mississippi River Valley alluvial (MRVA) aquifer and the Mississippi embayment aquifer system that includes several regional aquifers and confining units. Based on the distribution of groundwater use for...
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Groundwater is a vital resource in the Mississippi embayment of the central United States. An innovative approach using machine learning (ML) was employed to predict groundwater salinity—including specific conductance (SC), total dissolved solids (TDS), and chloride (Cl) concentrations—across three drinking-water aquifers of the Mississippi embayment. A ML approach was used because it accommodates a large and diverse set of explanatory variables, does not assume monotonic relations between predictors and response data, and results can be extrapolated to areas of the aquifer not sampled. These aspects of ML allowed potential drivers and sources of high salinity water that have been hypothesized in other studies to...
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Groundwater is a vital resource in the Mississippi embayment physiographic region (Mississippi embayment) of the central United States and can be limited in some areas by high concentrations of trace elements. The concentration of trace elements in groundwater is largely driven by oxidation-reduction (redox) processes. Redox processes are a group of biotically driven reactions in which energy is derived from the exchange of electrons. In groundwater, this commonly occurs through decomposition of organic matter (carbon) by microbes, which consumes dissolved oxygen (DO). Under low DO conditions, iron (Fe), manganese, and arsenic can dissolve from coatings on aquifer sediments and be released into groundwater. Therefore,...
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This dataset was compiled to summarize discharge measurements from several published groundwater and surface-water studies in the Ozarks of southern Missouri and northern Arkansas. The discharge measurements were part of numerous USGS studies to assess interaction between streams and groundwater aquifers. A gaining stream is described as a surface-water stream that gains water from the groundwater aquifer and a losing stream is described as a surface-water stream that loses water to the groundwater aquifer. This product is intended to be used in surface-water and groundwater investigations assessing water quantity, quality, and availability. The product includes flow-line data digitized along National Hydrography...
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Groundwater is a vital resource in the Mississippi embayment physiographic region (Mississippi embayment) of the central United States and can be limited in some areas by high concentrations of trace elements. The concentration of trace elements in groundwater is largely driven by oxidation-reduction (redox) processes. Redox processes are a group of biotically driven reactions in which energy is derived from the exchange of electrons. In groundwater, this commonly occurs through decomposition of organic matter (carbon) by microbes, which consumes dissolved oxygen (DO). Under low DO conditions, iron (Fe), manganese, and arsenic can dissolve from coatings on aquifer sediments and be released into groundwater. Therefore,...
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Groundwater is a vital resource in the Mississippi embayment physiographic region (Mississippi embayment) of the central United States and can be limited in some areas by high concentrations of trace elements. The concentration of trace elements in groundwater is largely driven by oxidation-reduction (redox) processes. Redox processes are a group of biotically driven reactions in which energy is derived from the exchange of electrons. In groundwater, this commonly occurs through decomposition of organic matter (carbon) by microbes, which consumes dissolved oxygen (DO). Under low DO conditions, iron (Fe), manganese, and arsenic can dissolve from coatings on aquifer sediments and be released into groundwater. Therefore,...
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Groundwater is a vital resource in the Mississippi embayment physiographic region (Mississippi embayment) of the central United States and can be limited in some areas by high concentrations of trace elements. The concentration of trace elements in groundwater is largely driven by oxidation-reduction (redox) processes. Redox processes are a group of biotically driven reactions in which energy is derived from the exchange of electrons. In groundwater, this commonly occurs through decomposition of organic matter (carbon) by microbes, which consumes dissolved oxygen (DO). Under low DO conditions, iron (Fe), manganese, and arsenic can dissolve from coatings on aquifer sediments and be released into groundwater. Therefore,...
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The Mississippi River Valley alluvial aquifer (MRVA) overlies and is bounded by several regional aquifers that make up the Mississippi embayment aquifer system (MEAS) in the central United States. The MRVA, which consists of Quaternary alluvium, is one of the most heavily pumped aquifers in the nation and is a major source of groundwater for irrigation. Large groundwater-level declines in portions of the aquifer have raised concerns about sustainable use of this important resource. An aquifer-scale assessment of groundwater-age categories based on tritium concentrations was completed to better understand groundwater availability and susceptibility. The presence of tritium, a radioactive isotope of hydrogen, in a...
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Groundwater is a vital resource in the Mississippi embayment physiographic region (Mississippi embayment) of the central United States and can be limited in some areas by high concentrations of trace elements. The concentration of trace elements in groundwater is largely driven by oxidation-reduction (redox) processes. Redox processes are a group of biotically driven reactions in which energy is derived from the exchange of electrons. In groundwater, this commonly occurs through decomposition of organic matter (carbon) by microbes, which consumes dissolved oxygen (DO). Under low DO conditions, iron (Fe), manganese, and arsenic can dissolve from coatings on aquifer sediments and be released into groundwater. Therefore,...
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This dataset was compiled to summarize discharge measurements from several published groundwater and surface-water studies in the Ozarks of southern Missouri and northern Arkansas. The discharge measurements were part of numerous USGS studies to assess interaction between streams and groundwater aquifers. A gaining stream is described as a surface-water stream that gains water from the groundwater aquifer and a losing stream is described as a surface-water stream that loses water to the groundwater aquifer. This product is intended to be used in surface-water and groundwater investigations assessing water quantity, quality, and availability. The product includes point data of discharge measurements digitized from...
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Groundwater is a vital resource in the Mississippi embayment of the central United States. An innovative approach using machine learning (ML) was employed to predict groundwater salinity—including specific conductance (SC), total dissolved solids (TDS), and chloride (Cl) concentrations—across three drinking-water aquifers of the Mississippi embayment. A ML approach was used because it accommodates a large and diverse set of explanatory variables, does not assume monotonic relations between predictors and response data, and results can be extrapolated to areas of the aquifer not sampled. These aspects of ML allowed potential drivers and sources of high salinity water that have been hypothesized in other studies to...
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Groundwater is a vital resource in the Mississippi embayment of the central United States. An innovative approach using machine learning (ML) was employed to predict groundwater salinity—including specific conductance (SC), total dissolved solids (TDS), and chloride (Cl) concentrations—across three drinking-water aquifers of the Mississippi embayment. A ML approach was used because it accommodates a large and diverse set of explanatory variables, does not assume monotonic relations between predictors and response data, and results can be extrapolated to areas of the aquifer not sampled. These aspects of ML allowed potential drivers and sources of high salinity water that have been hypothesized in other studies to...
    map background search result map search result map Ozark Plateaus seepage point dataset, southern Missouri and northern Arkansas, 1982-2006 Ozark Plateaus seepage flow-line dataset, southern Missouri and northern Arkansas, 1982-2006 Machine-learning model predictions and groundwater-quality rasters of specific conductance, total dissolved solids, and chloride in aquifers of the Mississippi embayment Prediction grids of pH for the Mississippi River Valley Alluvial and Claiborne Aquifers Machine-learning model predictions and groundwater-quality rasters of chloride in aquifers of the Mississippi Embayment Depth rasters in aquifers of the Mississippi Embayment Machine-learning model predictions and groundwater-quality rasters of specific conductance in aquifers of the Mississippi Embayment Machine-learning model predictions and groundwater-quality rasters of total dissolved solids in aquifers of the Mississippi Embayment Machine-learning model predictions and rasters of dissolved oxygen probability, iron concentration, and redox conditions in groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Depth rasters of redox conditions in groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Dissolved oxygen probability rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Iron concentration rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Redox zone rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Machine-learning model predictions and rasters of arsenic and manganese in groundwater in the Mississippi River Valley alluvial aquifer Groundwater age categories based on tritium concentrations in samples collected from the Mississippi River Valley alluvial aquifer and aquifers of the Mississippi embayment principal aquifer system Ozark Plateaus seepage point dataset, southern Missouri and northern Arkansas, 1982-2006 Ozark Plateaus seepage flow-line dataset, southern Missouri and northern Arkansas, 1982-2006 Groundwater age categories based on tritium concentrations in samples collected from the Mississippi River Valley alluvial aquifer and aquifers of the Mississippi embayment principal aquifer system Machine-learning model predictions and groundwater-quality rasters of specific conductance, total dissolved solids, and chloride in aquifers of the Mississippi embayment Prediction grids of pH for the Mississippi River Valley Alluvial and Claiborne Aquifers Machine-learning model predictions and groundwater-quality rasters of chloride in aquifers of the Mississippi Embayment Depth rasters in aquifers of the Mississippi Embayment Machine-learning model predictions and groundwater-quality rasters of specific conductance in aquifers of the Mississippi Embayment Machine-learning model predictions and groundwater-quality rasters of total dissolved solids in aquifers of the Mississippi Embayment Machine-learning model predictions and rasters of dissolved oxygen probability, iron concentration, and redox conditions in groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Depth rasters of redox conditions in groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Dissolved oxygen probability rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Iron concentration rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Redox zone rasters of groundwater in the Mississippi River Valley alluvial and Claiborne aquifers Machine-learning model predictions and rasters of arsenic and manganese in groundwater in the Mississippi River Valley alluvial aquifer